For now, the only "big" skip I found is this one:

Instead of going down and riding the elevator up, you can actually drop yourself in the acid and it will respawn you upstairs.

Not a huge time save, but it's very easy to do, just drop below in the intended way but instead of reaching the platform, spam the duplicate button on the cable and let yourself drown in the acid.

I actually discovered that on my first casual run by mistake lol